A scroll compressor is a certain type of compressor that is used to compress refrigerant for such applications as refrigeration, air conditioning, industrial cooling and freezer applications, and/or other applications where compressed fluid may be used. Such prior scroll compressors are known, for example, as exemplified in U.S. Pat. No. 6,398,530 to Hasemann; U.S. Pat. No. 6,814,551, to Kammhoff et al.; U.S. Pat. No. 6,960,070 to Kammhoff et al.; and U.S. Pat. No. 7,112,046 to Kammhoff et al., all of which are assigned to a Bitzer entity closely related to the present assignee. As the present disclosure pertains to improvements that can be implemented in these or other scroll compressor designs, the entire disclosures of U.S. Pat. Nos. 6,398,530; 7,112,046; 6,814,551; and 6,960,070 are hereby incorporated by reference in their entireties.
As is exemplified by these patents, scroll compressors assemblies conventionally include an outer housing having a scroll compressor contained therein. A scroll compressor includes first and second scroll compressor bodies. A first scroll compressor body is typically arranged stationary and fixed in the outer housing. A second scroll compressor body is movable relative to the first scroll compressor body in order to compress refrigerant between respective scroll ribs which rise above the respective bases and engage in one another. Conventionally the movable scroll compressor member is driven about an orbital path about a central axis for the purposes of compressing refrigerant. An appropriate drive unit, typically an electric motor, is provided usually within the same housing to drive the movable scroll member.
In some scroll compressors, it is known to have axial restraint, whereby the fixed scroll compressor body has a limited range of movement. This can be desirable due to thermal expansion when the temperature of the orbiting scroll compressor body and fixed scroll compressor body increases causing these components to expand. Examples of an apparatus to control such restraint are shown in U.S. Pat. No. 5,407,335, issued to Caillat et al., the entire disclosure of which is hereby incorporated by reference.
Typically, the outer housing is separated to include a high-pressure chamber and a low-pressure chamber by a separator plate. The first compressor member, i.e. the fixed compressor member, is typically positioned within the low-pressure chamber and is fluidly sealed to a port in the separator plate to communicate the high-pressure refrigerant exiting from the scroll compressor to the high-pressure chamber.
At startup, the pressure below the seal is higher than the pressure above the seal for a short period of time. This pressure imbalance causes the seal to move up and a seal spring carried within a seal jacket can be undesirably ejected from the seal jacket.
The present invention is directed towards improvements over the state of the art as it relates to the above-described features and other features of scroll compressors.